Transfusion

The first and, arguably, the most important spell of any hemomancers repertoire. You reach out your hand and try to force out the blood through the very skin of one creature you can see within range. The creature must make a constitution saving throw or take 1d8 necrotic damage. The damage is then transfused to your hand, at this point you can chose to give yourself temporary hit points, equal to the damage rolled, or transfer it into your blood point pool. 

This spell does not affect Constructs or other creatures that doesn't have blood.

This spell's damage increases by 1d8 when you reach 5th level (2d8), 11th level (3d8), and 17th level (4d8).